The present invention relates to a digital video tape recorder (digital VTR), and more particularly to a picture search control apparatus capable of easily searching for a desired picture.
When images are reproduced while a video tape is traveling at a high speed in a conventional digital VTR, the data tracks recorded on the tape are occasionally incongruous with the scanning tracks of the VTR heads. Thus, the heads are unable to reproduce an image having good picture quality.
To overcome such a problem, the current level of technology for recording image data signals on tape does not employ a conventional sequential recording method. Instead, to obtain optimum image clarity when the picture is formed with a collection of data samples read out by the heads during a high speed reproduction, a recording method has been used in which the alignment of the recorded data is altered or data constituting a whole picture is included in tracks scanned by the heads during the high speed reproduction. For example, in a disclosure by Matsushita Electric Co., Ltd. of Japan (PCF patent No. WO 90/02401), the entire contents of a flag memory is initialized to "1" values, prior to recording the data in memory, to thereby maximize the error correction capability of the outer decoder and improve the picture quality. If such a method is utilized, while perfect picture quality may be unobtainable, the necessary picture quality capable for at least locating a user-specified picture can be obtained during high speed reproduction.
However, in a system utilizing such methods as that described above, the user suffers eye fatigue due to the rapid movement of the images generated by the high speed reproduction. In addition, when the reproduction speed is thus increased, the user may or may not accurately discriminate procession of the picture.